Method and means for using low-compression fuels



Patented Mar. 2, 1926.

UNITED STATES PATENT OFFICE.

'rnomas MIDGLEY, 1a., or DAYTON, 01110, ASSIGNOR. BY MESNE ASSIGNMENTS, TO GE ERAL morons, CORPORATION, or DETROIT, MICHIGAN, A CORPORATION E DELAWARE.

METHOD AND MEANS FOR USING LOW-COMPRESSION EUELs.

No Drawing.

To all whom z't may concern:-

Be it known that ,I, THOMAS MmeLEY, Ir.,

a citizen of the United States of America,

residing, at Dayton, county of Montgomery, 5 and State of Ohio, have invented certain new and useful Improvements in Methods and Means for Using Low-Compression Fuels, of which the following is a full, clear, and exact description.

This invention relatesto the art of suppressing a fuel knock when a combustible gaseous mixture containing a low.compression fuel such, forexample, as kerosene and gasoline is burned under a-relat1vely h1gh pressure. The principal objects of this 1nvention are to employ bismuth compounds to suppress the fuel knock. I I

Kerosene has a critical compression, pressure of about 55 pounds. The critical com- 29 pression pressure of gasoline varies from about 75 poundsfor the commoner forms now marketed to about 125 pounds for aviation gasoline employed in airplane engines. These fuels are termed low compression fuels. When the vapors of any one of them is mixed with air, compressed to a compression pressure in excess of the normal critical compression pressure of the fuel, and burned, as in an internal combus- 30 tion engine, a 'fuel knock is produced.

I have found that vapors of bismuth compounds added to the. fuel-air mixture sup-- press this fuel knock and permit an increase in the engine compression pressure with a normal burning characteristic ofthe) fuel.

By way of anexample of one method of carrying out my invention, I dissolve 40 grams of triphenyl bismuthine B. (C H in 1 gallon of gasoline having a normal Application filed September 18, 1923. Serial No. 663,500.

critical compression pressure of about 7 5 4 pounds. This solution or high compression fuel is fed through a carburetor into the cylinder of an internal combustion engine havingv a compression pressure of about 100 pounds, the solution being vaporized and mixed with air as is common practice in engine operation. The gaseous high compression fuel is ignited and the engine operated without a fuel knock. The gasoline forms the fuel base and the bismuth compound increases the critical compression pressure of this base.

This process may be varied by changing the proportions according to the increase in critical compression pressure desired and by using other bismuth compounds in place of the triphenyl bismuthine. Among the com pounds of bismuth which may be employed are alkyl compounds such as triethyl bismuthine and tri-methyl bismuthine.

I prefer to employ the bismuth compounds which are soluble in the fuel to promote the mixing of the two. Blending agents may be employed if the bismuth compound does not dissolve readily in the fuel. The compound may .be added to the fuel-air mixture just before the latter is burned. v

1. A composition of matter comprising a low compression fuel; and a volatile bismuth compound incorporated therein and adapted to increase the critical compression pressure of the fuel.

2. A composition of matter comprising gasoline; and triphenyl bismuthine.

In testimony whereof I hereto affix my signature.

THOMAS MIDGLEY JR. 

